PWMAudioStreamPico

Author: pschatzmann

src/AudioPWM/PWMAudioBase.h

@@ -221,10 +221,10 @@ class PWMAudioStreamBase : public AudioPrint, public AudioBaseInfoDependent {
         // blocking write for an array: we expect a singed value and convert it into a unsigned 
         virtual size_t write(const uint8_t *wrt_buffer, size_t size){
             size_t available = min((size_t)availableForWrite(),size);
-            LOGD("write: %zu bytes -> %zu", size, available);
+            LOGD("write: %u bytes -> %u", (unsigned int)size, (unsigned int)available);
             size_t result = buffer->writeArray(wrt_buffer, available);
             if (result!=available){
-                LOGW("Could not write all data: %d -> %d", size, result);
+                LOGW("Could not write all data: %u -> %d", (unsigned int) size, result);
             }
             // activate the timer now - if not already done
             startTimer();

src/AudioPWM/PWMAudioMBED.h

@@ -2,14 +2,14 @@
 #pragma once
 #if defined(__arm__)  && __has_include("mbed.h")
 #include "AudioPWM/PWMAudioBase.h"
+#include "AudioTimer/AudioTimer.h"
 #include "mbed.h"
 
 namespace audio_tools {
 
 // forward declaration
 class PWMAudioStreamMBED;
 typedef PWMAudioStreamMBED PWMAudioStream;
-static PWMAudioStreamMBED *accessAudioPWM = nullptr; 
 
 /**
  * @brief Audio output to PWM pins for MBED based Arduino implementations
@@ -18,19 +18,17 @@ static PWMAudioStreamMBED *accessAudioPWM = nullptr;
  */
 
 class PWMAudioStreamMBED : public PWMAudioStreamBase {
-    friend void defaultPWMAudioOutputCallback();
 
     public:
 
         PWMAudioStreamMBED(){
             LOGD("PWMAudioStreamMBED");
-            accessAudioPWM = this;
         }
 
         // Ends the output
-        virtual void end(){
+        virtual void end() override {
             LOGD(LOG_METHOD);
-            ticker.detach(); // it does not hurt to call this even if it has not been started
+            ticker.end(); // it does not hurt to call this even if it has not been started
             is_timer_started = false;
 
             // stop and release pins
@@ -48,14 +46,15 @@ class PWMAudioStreamMBED : public PWMAudioStreamBase {
 
     protected:
         Vector<mbed::PwmOut*> pins;      
-        mbed::Ticker ticker; // calls a callback repeatedly with a timeout
+        TimerAlarmRepeating ticker; // calls a callback repeatedly with a timeout
 
         /// when we get the first write -> we activate the timer to start with the output of data
-        virtual void startTimer(){
+        virtual void startTimer() override {
             if (!is_timer_started){
                 LOGD(LOG_METHOD);
                 long wait_time = 1000000l / audio_config.sample_rate;
-                ticker.attach_us(defaultPWMAudioOutputCallback, wait_time);
+                ticker.setCallbackParameter(this);
+                ticker.begin(defaultPWMAudioOutputCallback, wait_time, US);
                 is_timer_started = true;
             }
         }
@@ -99,15 +98,17 @@ class PWMAudioStreamMBED : public PWMAudioStreamBase {
             float float_value = static_cast<float>(value) / maxOutputValue();
             pins[channel]->write(float_value);    // pwm the value is between 0.0 and 1.0 
         }
-      
+
+        /// timer callback: write the next frame to the pins
+        static inline void  defaultPWMAudioOutputCallback(void *obj) {
+            PWMAudioStreamMBED* accessAudioPWM = (PWMAudioStreamMBED*) obj;
+            if (accessAudioPWM!=nullptr){
+                accessAudioPWM->playNextFrame();
+            }
+        }
+
 };
 
-/// timer callback: write the next frame to the pins
-void  defaultPWMAudioOutputCallback() {
-    if (accessAudioPWM!=nullptr){
-        accessAudioPWM->playNextFrame();
-    }
-}
 
 } // Namespace
 

src/AudioPWM/PWMAudioRP2040.h

@@ -12,7 +12,6 @@ namespace audio_tools {
 // forwrd declaratioin of callback
 class PWMAudioStreamPico;
 typedef PWMAudioStreamPico PWMAudioStream;
-//bool defaultPWMAudioOutputCallbackPico(repeating_timer* ptr);
 
 /**
  * @brief Rasperry Pico Channel to pin assignments
@@ -47,10 +46,8 @@ class PWMAudioStreamPico : public PWMAudioStreamBase {
         /// Ends the output -> resets the timer and the pins
         void end() override {
             LOGD(LOG_METHOD);
+            ticker.end(); // it does not hurt to call this even if it has not been started
             is_timer_started = false;
-            if (!cancel_repeating_timer(&timer)){
-                LOGE("cancel_repeating_timer failed")
-            }
             for(auto pin : pins) {
                 if (pin.gpio!=-1){
                     pwm_set_enabled(pin.slice, false);
@@ -60,10 +57,16 @@ class PWMAudioStreamPico : public PWMAudioStreamBase {
 
     protected:
         Vector<PicoChannelOut> pins;      
-        repeating_timer_t timer;
+        TimerAlarmRepeating ticker;
 
         virtual void startTimer() override {
-            //LOGI(LOG_METHOD);
+            if (!is_timer_started){
+                LOGD(LOG_METHOD);
+                long wait_time = 1000000l / audio_config.sample_rate;
+                ticker.setCallbackParameter(this);
+                ticker.begin(defaultPWMAudioOutputCallbackPico, wait_time, US);
+                is_timer_started = true;
+            }
             is_timer_started = true;
         }
 
@@ -128,15 +131,6 @@ class PWMAudioStreamPico : public PWMAudioStreamBase {
         }
 
         void setupTimer() override {
-            LOGD(LOG_METHOD);
-            // setup timer
-            uint32_t time = 1000000UL / audio_config.sample_rate;
-            LOGI("->Timer value %ld us", time);
-            if (!add_repeating_timer_us(-time, &defaultPWMAudioOutputCallbackPico, this, &timer)){
-                LOGE("Error: alarm_pool_add_repeating_timer_us failed; no alarm slots available");
-            } else {
-                LOGI("repeating timer has started");
-            }
         }
 
         /// The pico supports max 16 pwm pins
@@ -155,12 +149,9 @@ class PWMAudioStreamPico : public PWMAudioStreamBase {
         }
 
         // timed output executed at the sampleRate
-        static bool defaultPWMAudioOutputCallbackPico(repeating_timer* ptr) {
-            PWMAudioStreamPico *self = (PWMAudioStreamPico*)  ptr->user_data;
-            //if (self!=nullptr){
-                self->playNextFrame();
-            //}
-            return true;
+        inline static void defaultPWMAudioOutputCallbackPico(void* ptr) {
+            PWMAudioStreamPico *self = (PWMAudioStreamPico*)  ptr;
+            self->playNextFrame();
         }
 
 };

src/AudioTimer/AudioTimerRP2040.h

@@ -69,12 +69,11 @@ class TimerAlarmRepeatingRP2040 : public TimerAlarmRepeatingDef{
     protected:
         alarm_pool_t *ap = nullptr;
         repeating_timer_t timer;
-        my_repeating_timer_callback_t instanceCallback;
+        my_repeating_timer_callback_t instanceCallback=nullptr;
 };
 
 typedef  TimerAlarmRepeatingRP2040 TimerAlarmRepeating;
 
-
 }
 
 

src/AudioTools/AudioStreams.h

@@ -259,7 +259,7 @@ class GeneratedSoundStream : public AudioStreamX, public AudioBaseInfoSource {
 
   /// privide the data as byte stream
   size_t readBytes(uint8_t *buffer, size_t length) override {
-    LOGD("GeneratedSoundStream::readBytes: %zu", length);
+    LOGD("GeneratedSoundStream::readBytes: %u", (unsigned int)length);
     return generator_ptr->readBytes(buffer, length);
   }